/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.tools;

import org.apache.iotdb.commons.file.SystemFileFactory;
import org.apache.iotdb.db.engine.storagegroup.TsFileResource;
import org.apache.iotdb.db.utils.DateTimeUtils;
import org.apache.iotdb.tsfile.fileSystem.FSFactoryProducer;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.*;

public class IoTDBDataDirViewer {

    public static void main(String[] args) throws IOException {
        String[] data_dir;
        String outFile = "IoTDB_data_dir_overview.txt";
        if (args.length == 0) {
            String path = "data/data";
            data_dir = path.split(","); // multiple data dirs separated by comma
        } else if (args.length == 1) {
            data_dir = args[0].split(",");
        } else if (args.length == 2) {
            data_dir = args[0].split(",");
            outFile = args[1];
        } else {
            throw new IOException("Invalid parameters. Please check the user guide.");
        }
        System.out.println("output save path:" + outFile);
        System.out.println("data dir num:" + data_dir.length);
        try (PrintWriter pw = new PrintWriter(new FileWriter(outFile))) {
            for (String dir : data_dir) {
                File dirFile = FSFactoryProducer.getFSFactory().getFile(dir);
                File[] seqAndUnseqDirs = dirFile.listFiles();
                if (seqAndUnseqDirs == null || seqAndUnseqDirs.length != 2) {
                    throw new IOException(
                            "Irregular data dir structure.There should be a sequence and unsequence directory "
                                    + "under the data directory "
                                    + dirFile.getName());
                }
                List<File> fileList = Arrays.asList(seqAndUnseqDirs);
                fileList.sort((Comparator.comparing(File::getName)));
                if (!"sequence".equals(seqAndUnseqDirs[0].getName())
                        || !"unsequence".equals(seqAndUnseqDirs[1].getName())) {
                    throw new IOException(
                            "Irregular data dir structure.There should be a sequence and unsequence directory "
                                    + "under the data directory "
                                    + dirFile.getName());
                }

                printlnBoth(pw, "|==============================================================");
                printlnBoth(pw, "|" + dir);
                printlnBoth(pw, "|--sequence");
                printFilesInSeqOrUnseqDir(seqAndUnseqDirs[0], pw);
                printlnBoth(pw, "|--unsequence");
                printFilesInSeqOrUnseqDir(seqAndUnseqDirs[1], pw);
            }
            printlnBoth(pw, "|==============================================================");
        }
    }

    private static void printFilesInSeqOrUnseqDir(File seqOrUnseqDir, PrintWriter pw)
            throws IOException {
        File[] storageGroupDirs = seqOrUnseqDir.listFiles();
        if (storageGroupDirs == null) {
            throw new IOException(
                    "Irregular data dir structure.There should be database directories under "
                            + "the sequence/unsequence directory "
                            + seqOrUnseqDir.getName());
        }
        List<File> fileList = Arrays.asList(storageGroupDirs);
        fileList.sort((Comparator.comparing(File::getName)));
        for (File storageGroup : storageGroupDirs) {
            printlnBoth(pw, "|  |--" + storageGroup.getName());
            printFilesInStorageGroupDir(storageGroup, pw);
        }
    }

    private static void printFilesInStorageGroupDir(File storageGroup, PrintWriter pw)
            throws IOException {
        File[] files = storageGroup.listFiles();
        if (files == null) {
            throw new IOException(
                    "Irregular data dir structure.There should be timeInterval directories under "
                            + "the database directory "
                            + storageGroup.getName());
        }
        List<File> fileList = Arrays.asList(files);
        fileList.sort((Comparator.comparing(File::getName)));
        for (File file : files) {
            printlnBoth(pw, "|  |  |--" + file.getName());
            printFilesInTimeInterval(file, pw);
        }
    }

    private static void printFilesInTimeInterval(File timeInterval, PrintWriter pw)
            throws IOException {
        File[] files = timeInterval.listFiles();
        if (files == null) {
            throw new IOException(
                    "Irregular data dir structure.There should be tsfiles under "
                            + "the timeInterval directories directory "
                            + timeInterval.getName());
        }
        List<File> fileList = Arrays.asList(files);
        fileList.sort((Comparator.comparing(File::getName)));
        for (File file : files) {
            printlnBoth(pw, "|  |  |  |--" + file.getName());

            // To print the content if it is a tsfile.resource
            if (file.getName().endsWith(".tsfile.resource")) {
                printResource(file.getAbsolutePath(), pw);
            }
        }
    }

    private static void printResource(String filename, PrintWriter pw) throws IOException {
        filename = filename.substring(0, filename.length() - 9);
        TsFileResource resource = new TsFileResource(SystemFileFactory.INSTANCE.getFile(filename));
        resource.deserialize();
        // sort device strings
        SortedSet<String> keys = new TreeSet<>(resource.getDevices());
        for (String device : keys) {
            printlnBoth(
                    pw,
                    String.format(
                            "|  |  |  |  |--device %s, start time %d (%s), end time %d (%s)",
                            device,
                            resource.getStartTime(device),
                            DateTimeUtils.convertMillsecondToZonedDateTime(resource.getStartTime(device)),
                            resource.getEndTime(device),
                            DateTimeUtils.convertMillsecondToZonedDateTime(resource.getEndTime(device))));
        }
    }

    private static void printlnBoth(PrintWriter pw, String str) {
        System.out.println(str);
        pw.println(str);
    }
}
